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The impact of polyols on water structure in solution: a computational study
Regina Politi1, Liel Sapir, Daniel Harries
1Institute of Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel.
The Journal of Physical Chemistry. A
|May 13, 2009
Summary
Polyalcohols alter water
Area of Science:
- Physical Chemistry
- Biophysical Chemistry
Background:
- Water's hydrogen bond network is crucial for its unique properties.
- Polyols are known to stabilize macromolecules, but their effect on water structure is not fully understood.
Purpose of the Study:
- To investigate how different polyalcohols impact water structuring in concentrated solutions.
- To correlate polyol structure with changes in water's hydrogen bond network.
Main Methods:
- Molecular dynamics simulations were employed.
- Six polyols with varying hydroxyl group numbers and structures were simulated in aqueous solutions.
- The tetrahedral order parameter was used to assess water network order.
Main Results:
- Polyols distort the hydrogen bond network order of water compared to pure water.
- This distortion depends on the number of hydroxyl groups and the polyol's conformation.
- Hydrogen bonds involving polyols are less linear than water-water hydrogen bonds.
Conclusions:
- Polyol solvation introduces disorder into the water structure due to competition for hydrogen bonds.
- This understanding can inform the use of polyols as stabilizers for biomacromolecules like proteins.
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